#include <stdio.h> 
//验证表达式getchar() != EOF的值是0还是1
//getchar() == EOF 为0
//getchar() != EOF 为1

int main()
{
    int c;
    while(c = (getchar() != EOF))
        printf("%d\n", c);
    printf("%d - at EOF\n", c);

    return 0;
}